Is it possible to modify a Mac to select a whole word with a single click (or a modifier key) vs double click?
Control-Click will highlight the whole word (as user3439894 has pointed out) - to prevent the context menu staying open without you having to press escape or clicking away, you simply need hold the mouse down for about a second.
- Press Control key down
- Click on word, holding mouse down
- Release Control key or mouse - the context menu should disappear, but the word will remain selected